Competition among insulin makers is intense. In most cases, manufacturers realize that various forms of insulin are well matched in clinical efficacy and safety by competing insulin makers. The only real differentiator among the products may be how the insulin is delivered. In fact, these manufacturers spend a tremendous amount of design research, engineering, testing, and market research resources in producing a delivery device that patients will find relatively comfortable, easy to use, and portable (see example). It brings to mind an executive for a major insulin producer who I had repeatedly seen stabbing himself with a pen-type injection device (without insulin) to demonstrate to others that the delivery system and the narrow-gauge needle was about as pain-free as possible to engineer.

This raises the question of whether a patient with diabetes mellitus whose glycemic levels are under control are actually loyal to the insulin brand or its delivery system. In reality, however, health plans and insurers pay far more attention to the insulin formulation than to the insulin delivery device in making coverage decisions. In some cases, they may cover only certain types of delivery systems, yet this seems to contradict the precepts of value-based benefits (providing best access to interventions that are proven to improve diabetes control and/or adherence). Health plans and insurers may instead focus on other aspects of the insulin itself, such as whether it has a relatively lower risk of hypoglycemic events.

A few years ago, the question about which basal insulin to cover was straightforward, usually amounting to pricing, rebates, and existing marketshare (e.g., how difficult it might be to switch the majority of patients who were taking Lantus® to Levemir®). This was no different than other competitive drug categories. The introduction of the first follow-on (or let’s face it, biosimilar) insulin glargine (Basaglar®) has added new impetus to this discussion. Lilly, the company licensing Basaglar, won a couple of big coverage victories for 2017 over Sanofi’s Lantus, including CVS Health and UnitedHealthcare. The partnership of Merck and Samsung Bioepis hope to receive a positive FDA decision on their insulin glargine biosimilar in the third quarter of this year. Lilly, a veteran of the insulin wars, promotes the use of its existing KwikPen® system for Basaglar. Should Merck get a positive decision, it will market another pen-delivery system. (For the record, Merck is not a complete stranger to the insulin market. It does have an insulin product marketed to the veterinary sector, with its own pen-delivery system [VetPen®]). This raises the question of whether the biosimilar must be paired with its own, perhaps prefilled pen-delivery device and whether it results in the same or similar patient satisfaction ratings. This could have implications for adherence and thus glycemic control.

The US continues to lag behind Europe in terms of pen-injector use (more than two-thirds of patients in Europe use pen-based systems, whereas only 15% use pens in the US), where needles and syringes still dominate. The reasons for this are likely related to reimbursement or patient cost sharing. For those using needles and syringes, the payer’s preference for insulin glargine is more straightforward.

However, as the patents of this and other insulin analog molecules expire, it is reasonable to expect the availability of biosimilar or follow-on copies to increase, making the drug-delivery system pairing even more important.